An apparatus as discussed above is known from European patent EP-B1-0.223,317. In this known apparatus that which is needed for pressing the belt/tread assembly and the carcass with the beads and the side walls is realized by a pressure roller unit with a static pressing roller with at least one roller or group of coaxial rollers radially movable through the gate in the passage part. In this known apparatus the transfer unit stays in place around the carcass drum during pressing, so that a relatively short period is needed for the manufacture of a green radial tire.
By a carcass drum can be understood a carcass construction drum for a carcass with beads and side walls or a drum for expanding an airtight carcass with beads and side walls.
Green radial tires manufactured by apparatuses of the type as named in the preamble can be divided into so-called tread over sidewall construction and sidewall over tread construction. These two constructions will henceforth be referred to as TOS (tread over sidewall) and SOT (sidewall over tread) respectively.
In the case of a radial SOT pneumatic tire after the tread/belt assembly has been placed on the carcass with beads and sidewalls, the sidewalls are bent in such a way that they cover the edges of the tread after which the mutual pressing of the tread/belt assembly against the carcass with beads and sidewalls takes place with the help of the pressure roller unit. For some tire constructions it is in this case desirable to roll the sidewalls over the entire length of the bead up to the so-called shoulder of the green radial pneumatic tire.
In the case of a radial TOS pneumatic tire the carcass is expanded together with the sidewalls before the tread/belt assembly can be placed and the rolling on by the pressure roller unit takes place.
Nowadays more and more radial pneumatic tires are manufactured having a large tire width and a very low tire section height. Particularly for passenger cars the demand for these so-called `High Performance` tires has increased.
In practise it has emerged that the apparatus known from EP-B1-0.223.317 especially in the manufacture of very wide radial pneumatic tires, TOS as well as SOT, does not offer optimal manufacturing efficiency. Furthermore, the wish to roll the sidewalls over the entire length of the bead up to the shoulder of the radial pneumatic tire cannot be fulfilled.